The present invention relates to a heat exchanger and also to a channel member for a heat exchanger.
The invention has been developed primarily for use with air conditioning heat exchangers and will be described hereinafter with reference to that application. It will be appreciated, however, that the invention is not limited to that particular field of use and is also applicable to other heat exchangers and heat transfer between fluids other than air.
Known heat exchangers generally include two separate fluid flow paths which are adjacent to each other such that heat can be transferred from one path to the other. When such heat exchanges are configured for use in large multistorey building they are bulky and/or expensive to manufacture. This is in part due to the required capacity, complex manufacturing techniques and/or the materials from which the exchanger is produced. Additional difficulties are introduced by the requirement to seal each fluid flow path from each other, while maintaining acceptable thermal transfer properties.
It is an object of the present invention, at least in the preferred embodiments, to overcome or substantially ameliorate one or more of the disadvantages of the prior art.
According to a first aspect of the invention there is provided a heat exchanger including:
a housing extending between a first end and a second end;
a first housing opening and a second housing opening disposed proximate said first end;
a third housing opening and a fourth housing opening disposed proximate said second end;
a plurality of like channel members, each including a heat exchanging wall and a peripheral flange extending outwardly from the wall for maintaining the wall in a spaced apart configuration from a like wall of an adjacent like channel member, wherein each flange defines a first channel member opening and a second channel member opening, and said channel members are arranged within the housing such that each of the first channel member openings are in communication with either the first or the second housing opening and each of the second channel member openings are in communication with either the third or fourth housing opening, thereby defining a plurality of first fluid flow paths between the first and third housing openings and a separate plurality of second fluid flow paths between the second and fourth housing openings.
Preferably, the channel members are alternately stacked such that adjacent flow paths alternate between first flow paths and second flow paths.
Preferably each channel member is disposable within the housing in:
a first orientation wherein the first channel member opening is in communication with the first housing opening and the second channel opening is in communication with the third housing opening; or
a second orientation wherein the first channel member opening is in communication with the second housing opening and the second channel member opening is in communication with the fourth housing opening.
According to a second aspect of the invention there is provided a heat exchanger including:
a housing extending between a first end and a second end;
a first housing opening and a second housing opening disposed proximate said first end;
a third housing opening and a fourth housing opening disposed proximate said second end; and
a plurality of like channel members arranged within the housing to define a plurality of first fluid flow paths between the first and third housing openings and a separate plurality of second fluid flow paths between the second and fourth housing openings, said first and second flow paths presenting substantially equal fluid flow resistance.
Preferably the housing includes a top face, a bottom face and two opposed side faces joining the opposite edges of top face and the bottom face. In one embodiment, the first and fourth housing openings are respectively disposed in said first and second ends, the third housing opening is disposed in the bottom face adjacent the second end and the second housing opening is disposed in the top face adjacent the first end. In another embodiment the first and second housing openings are disposed in the first end and the third and fourth housing openings are disposed in the second end.
According to a third aspect of the invention there is provided a channel member for a heat exchanger, said channel member including a heat exchanging wall and a peripheral flange extending outwardly from the wall for maintaining the wall in a spaced apart configuration from a like wall of a like channel member, wherein the flange defines a first channel member opening and a second channel member opening such that a plurality of like channel members are stackable so as to define a plurality of separate flow paths between said first and second channel member openings.
Preferably, the wall is rectangular and includes two opposed broad sides and two opposed short sides joining the broad sides. In one embodiment the first channel member opening is disposed along one short side and the second channel member opening is disposed along one broad side and adjacent to the other short side. In another embodiment the first channel member opening is disposed on a short side and the second channel member opening is disposed on the opposite short side.
Preferably also, the flange includes a lip for facilitating the abutment of the channel member to an adjacent like channel member. Alternatively, the flange supports a second heat exchanging wall opposed to and spaced apart from the first.
In a preferred form, the channel member includes a plurality of spaced apart baffles for increasing the length of the flow paths. More preferably, the baffles are parallel and alternately extend from the respective broad sides of the wall. More preferably, each baffle is integrally formed with the like baffle of an adjacent channel member.
According to a fourth aspect of the invention there is provided a method of constructing a heat exchanger including the steps of:
forming a plurality of channel members, each having a heat exchanging wall and a peripheral flange extending outwardly from the wall for maintaining the wall in a spaced apart configuration from a like wall of an adjacent like channel member, wherein the flange defines a first channel member opening and a second channel member opening;
forming a housing extending between a first and a second end and having a first and a second housing opening disposed proximate said first end and a third and fourth housing opening disposed proximate said second end;
arranging said channel members within said housing such that each of the first channel member openings are in communication with either the first or second housing member opening, and each of the second channel member openings are in communication with either the third or fourth housing opening, thereby defining a plurality of first fluid flow paths between the first and third housing openings and a separate plurality of second fluid flow paths between the second and fourth housing openings.
Preferably, the housing is formed by stamping a housing blank from a planar sheet material and folding said housing blank to form a housing. Similarly, the channel members are preferably formed by stamping a channel blank from a planar sheet material and folding said housing blank to form a channel member.
According to another aspect of the invention there is provided a method of exchanging heat between a first fluid and a second fluid, said method including circulating said first and second fluids through a respective plurality of first and second fluid flow paths defined by a plurality of stacked like channel members, each channel member having a heat exchanging wall and a peripheral flange extending outwardly from the wall for maintaining the wall in a spaced apart configuration from a like wall of an adjacent like channel member, wherein the flange of each channel member defines a first channel member opening for receiving fluid and a second channel member opening for exhausting fluid and whereby adjacent flow paths alternate between first and second flow paths, thereby to promote heat exchange across said heat exchanging walls.
Preferably, the first and second flow paths present substantially equal fluid flow resistance.